Longitudinal Frequencies of Blood Leukocyte Subpopulations Differ between NOD and NOR Mice but Do Not Predict Diabetes in NOD Mice

Immune phenotyping provides insight into disease pathogenesis and prognostic markers. Trajectories from age of 4 to 36 weeks were modeled for insulin autoantibodies and for leukocyte subpopulations in peripheral blood from female NOD (n = 58) and NOR (n = 22) mice. NOD mice had higher trajectories of insulin autoantibodies, CD4⁺ and CD8⁺ T lymphocytes, B lymphocytes, IgD⁺IgM^- B lymphocytes, and NK cells and lower trajectories of CD4⁺CD25⁺ T lymphocytes, IgM⁺ B lymphocytes, granulocytes, and monocytes than NOR mice (all p < 0.001). Of these, only the increased IAA trajectory was observed in NOD mice that developed diabetes as compared to NOD mice that remained diabetes-free. Therefore, the profound differences in peripheral blood leukocyte proportions observed between the diabetes-prone NOD mice and the diabetes-resistant mice do not explain the variation in diabetes development within NOD mice and do not provide markers for diabetes prediction in this model.